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Well guys . . .I`m sure you`ll deliver on this one. You can get a great sounding DP but when you hit those high notes . . . .oh, dear. Oh dear oh dear oh dear . . (edited version) and the final octave - Don`t even think of going there!Best cheap recommendations? Doesn`t even have to have inbuilt amp or speakers, but it helps!

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"I'm playing all the right notes � but not necessarily in the right order." Eric Morecambe

I've been using digital keyboards since they came out and even the earliest ones had excellent top notes and excellent bottom notes, it seemed the hardest tones to recreate were the ones in the octave below middle C.

If you don't mind, I'm not going to do the research for you to provide the name and model of the cheapest keyboard with stretch tuning.

I thought it was common knowledge, folks When you tune a piano, you`ll use forks which give a certain frequency. You`ll get a dozen in the box. Then you tune on the octaves until you get to the top end of the keyboard. It then needs to be stretched beyond the harmonic frequency of the octave in order to sound in tune and possess that brilliance! Really does . . .every grand or upright acoustic will be tuned thus originally in the old fashioned way (digital tuning devices will be used now, I should think). Certainly, 20 years or so ago, Technics had digitals on the market which had this. . . for further reading,see this link. http://en.wikipedia.org/wiki/Stretched_tuning

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"I'm playing all the right notes � but not necessarily in the right order." Eric Morecambe

I thought it was common knowledge, folks When you tune a piano, you`ll use forks which give a certain frequency. You`ll get a dozen in the box. Then you tune on the octaves until you get to the top end of the keyboard. It then needs to be stretched beyond the harmonic frequency of the octave in order to sound in tune and possess that brilliance! Really does . . .every grand or upright acoustic will be tuned thus originally in the old fashioned way (digital tuning devices will be used now, I should think). Certainly, 20 years or so ago, Technics had digitals on the market which had this. . . for further reading,see this link. http://en.wikipedia.org/wiki/Stretched_tuning

There are 2 main reasons for stretch tuning.

1, For the piano. (inharmonicity) Piano strings have lots of harmonics in them. Some of them, especially at the lower end of the range, have harmonics which are out of tune with the higher notes of the piano. Stretch tuning alters these lower notes to try to bring these out of tune harmonics into tune with the higher notes on the piano. In doing this, low strings that are quite thick compared to their length end up being tuned flat. The thicker the strings get, the flatter they tend to become - hence the term "stretch tuning".

2. For the human ear. The human ear doesn't have a linear response to frequency. The perception of pitch at the low and high limits of the piano are not as accurate as the middle part of the keyboard. This is due to a certain amount of inefficiency in the anatomy of the ear itself. It is simply designed for a middle range - where most sounds occur, especially human voices. Low notes sound more true to their middle octave counterparts when they are tuned slightly flat. High notes sound more true when they are tuned slightly sharp.

However - not all humans are the same in this respect. While most humans are equal in their desire not to hear inharmonicity in their piano, humans vary quite a bit in terms of the efficiency of their ears. To some, the stretch needs to be stronger than others depending on how sharp or flat they hear those upper and lower notes. The ideal of course is if you are happy with the amount of stretch the piano's inharmonicity compensation gives. That means you aren't acting against what is ideal for the piano in terms of harmonics being in tune with the middle notes.

People need less additional stretch over what was added for harmonicity, probably have more efficient ears. The high notes don't need much stretching - they really aren't that high compared to the range of human hearing and shouldn't need to be stretch much, if at all. Bass notes are more problematic for the ear because they are getting close to the lower limit of human hearing. The inefficiency is greater there.

In terms of DPs, the inharmonicity part has already been done - pretty much only on the bass side. But they usually don't adjust for the individual desires for stretch at the outer octaves. That's where somebody might want an adjustable stretch tuning. Be warned though, when you stretch that tuning yourself, you are going to be working against the piano that was sampled - you might hear the fundamental frequencies as more accurate (especially as single notes), but when you play chords, you might get some unpleasant clashes because too many harmonics are fighting with the middle notes.

Personally, I have never liked the stretch tuning adjustments on DPs, they do more harm than good in my opinion. Most DP makers do a good job of adjusting for inharmonicity - which they should because if the original acoustic piano that they sampled was well tuned, they really shouldn't have to compensate anything beyond that - the inharmonicity adjustment has already been done!

Most DP samples are done from very large acoustic pianos so the inharmonicity is fairly low anyway. I actually doubt you would add much stretch manually because it will just make other things worse.

Peter, do you hear the extreme upper and low notes as being badly out of tune?

The low notes seem fine, Ando, but the upper are, I`d say, nearly a semitone out at the top. This has been the case with every digital I`ve had, even the short scale CLP250 (all cheapish ones); but with none of my acoustic pianos. Its also noticeable on the old Lowrey Holiday organs (popular in the 1970`s)when hitting the high notes sounded like you were strangling the cat. It wasn`t apparant on the tonewheel Hammonds.I`m gonna see if the Wise And Wonderful One making the coffee hears it the same as me . . . Appreciate your responses.

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"I'm playing all the right notes � but not necessarily in the right order." Eric Morecambe

"a minimum wage Eastern European shop assistant" ha ha! They are good lookers, no doubt about it. But it was the wife I was talking of. She agrees woth me, for once. The top c is nearly a semitone out; it gets progressively less so as you descend the scale. Try playing an arpeggio with both hands, firstly using the same notes a few octaves apart, then play the same arpeggio with the right hand sharpened a semitone.

Maybe most DP`s have compensated for this beyond a certain price range, and don`t feel the need to publish `cos it`s expected. ..

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"I'm playing all the right notes � but not necessarily in the right order." Eric Morecambe

I understand what you are saying. I thought most DPs had a stretch tuning option and then there are DPs out there that provide some user variable parameters with the tuning. Certainly the V-Piano for instance lets you tune each note (and indeed each string I believe) and whilst I know it is very expensive there will be others at a lower price that offer some flexibility in this regard. Software pianos usually have the facility to tune individual notes too.

I have to write a few words here. I've encountered many piano tuners in my lifetime and I have never encountered one who used 12 tuning forks. They bring one, period.

Back when I was 21 and bought my brand spanking new 48" Yamaha upright (U1D?) the tuner stretched the top few notes so much that there were almost a half step sharp.

Since this was rather obvious to me I now think the tuner really couldn't hear that well in that top range. I also think that just like musicians, tuners also have their share of hearing loss especially at higher frequencies.

The process of getting the pitches for a digital instrument is very complex, it can/must interplay with many other aspects of the instruments: sympathetic string resonance, key specific noises, reverb effects (instrument body + ambience) good implementations takes them all into account correctly.

The Pitch definition process involves the following steps:

1. Acoustical tuning of the of the sampled original (physical instrument)2. Sampling of the sound of single keys (not individual strings) with micprophones (many choises for microphone placement and settings, multiple mics, in the upper single strings while muted others, isolating level of noises, instrument compound resonances)3. Process the samples digitally, mixing/blending microphone inputs, apply measurements, finalising pitch for each individual sample (for each key there can be a lot - with and without sustain, una corda, then release samples, even noises, much of them individually handled for the separate velocity layers), looping, etc... 4. Add Tuning tables to the instrument, this involves adding - pitch correction tables (over all of the 88(or nn) keys, can even be layer or sample specific) this is optional to be able to make easier correction by SW-Updates afterwards in the later lifecycle of the product - stretch table over all of the 88(or nn) keys, - tuning tables scale tuning (offsets within an octave to be applyed for all the octaves in the instrument). 5. Give some setting options available for users (along with the built-in rules governing their behaviour with each possible combination of them) to the features and sell the instrument with some presets. This can include editing possibilities for the stretch and tuning tables, or simply chosing between stretch characterisitcs (flat, normal, wide, wider,...) 6. The user can chose setting of the options (among them selecting the stretch tuning table to be applied)

There are a plenty of conceivable pitfalls.

One of them is to apply measurements to the sampled instrument (in step 3.) These measurements are even more problematic than what a piano tuner is doing: he is muting the strings for the just tuned key but one, but sampled keys all of them are sounding (together 3, 2, only some deepest bass strings are single strings)- rendering measurement more difficult and less accurate.

And how to deal with stretching especially: after you have sampled a stretch tuned acoustic, you have to un-stretch-it to be able to apply different stretch tables (or flat). How will you determine the original stretch table to be able to unstretch-it - a difficult decision. (The most accurate method seems to apply measurements of the original tuning of the instrument based on single string measurements.)

If You have ever used a professional tuning Tool (SW Tuner), You will know, that to determine pitch You have to choose from a plenty of setting to be able to express the very complex overtone characteristic of a string (for one single velocity only) with a single cent value (which overtones to take into account, with which weighting - latter being mostly a built in feature in the algorhytm...).

Then most importantly pitch is typically changing throughout the one minute or so decaying of an excited single string (most dramatically during the attack phase - but which is the only sound with a very pronounced staccato note!). But You can only chose one pitch for a single key (well, on accoustic for a single string - on digital you have to choose it separately for the component samples)!

The overtone characteristics heavily influenced by copper (double/tripple) wired bass strings: these result in anomalies (with "out of tunes" overtones), for which pitch correction is a rudimentary tool only (in the stretch direction) - just better than none.

Large concert grands have a smoother stretch table (perhaps pardoxically), because not needed to be such havily wired as shorter strings in a smaller body (in chamber grands or smaller uprights).

In the upper compartment you have to deal with the phenomenon of undamped strings, which are a challenge for the sampling process as well - and the later need for key corrections.

Your own hearing (as mine) is the main pitfall: percieving musical pitch is even a more complex process than physical pitch definition. Your abilities to percieve sharply, to process and to compensate involve conflicting components and probably variyng with time (age, training, tiredness), making tuning prefrences so elusive.

Therefore finding of a right "temperament" was often like a war of religions, having some temperament specialists historically proposing or applying more than one or many different temperaments as the right one notoriously during their own lifetime. (Werckmeister, Neidhardt, Kirnberger, Sorge, Marpurg, Bendeler, Young...and some recently very active "discoverers" - I don't want to name them. I myself am now very cautios for the same reason and relactant publishing my own results on this area after doing some intensive work investigating and proposing relevant temperaments for historic composers.)

Sorry, perhaps too much of background, but a partial truth can easily be a lie. However truth is always approximative too - You cannot tell the whole reality and there can be simple but good approximations.

Briefly: probably most even cheap sampled piano sounds are stretched (due to the fact that their original acuoustic are stretched.) Stretch is the default - to be able to chose others (flat, wide, wider, etc. ) is extra.

If You have some special stretch setting needs, it seems You have to go with Roland or KAWAI - but full features are available only in their higher product range, probably above USD 1200-1500 and setting might be inconvenient.

Most DP makers do a good job of adjusting for inharmonicity - which they should because if the original acoustic piano that they sampled was well tuned, they really shouldn't have to compensate anything beyond that - the inharmonicity adjustment has already been done!

Many years ago, when some piano tuners first started using strobe tuners, I ran into the phenomenon that the guy who used a tuning fork and his ear created a better sounding tuned piano than the guy who used the strobe to assure that tuning was "perfect." (Whether he made any adjustments whatsoever for "stretching," I don't know.)

but you can see how complicated the issue is right from their own web page, where they boast of the feature this way: "Wide Selection of Pre-Programmed Stretch Files - tables with optimized tunings for all piano types and sizes takes the drudgery out of piano tuning! Up to 31 additional files may be programmed by the user."

Indeed, there is no single amount of stretching you can build into an automated tuning system. You can apparently do a good estimate if you know the type and size of piano, which allows them to build in what they feel are settings that should work well in most cases, but ultimately, I think nothing is going to beat a good set of ears.

But you bring up an interesting issue. How are the originally sampled pianos tuned? If I were going to sample a piano with the intent of playing it back on a system that would use separate samples for each of the 88 keys, I might employ stretch tuning on the acoustic to assure that that piano sounded its best before sampling the 88 keys. But if I were going to create a set of samples to include in an instrument where a single sample is likely to itself be stretched and used over a number of keys, might that not create more problems than it solves? And what about non-dedicated DPs, where you may layer piano and other sounds, which themselves, are not stretched? That could be another case where you might prefer your samples to be "true" pitch.

So it's an interesting question… do DP makers necessarily sample a stretch-tuned piano to begin with? Or do they tune each note true, and then, if desired, make adjustments to the pitch after the fact electronically? And if the latter, if they provide stretch tuning, are they creating that stretch tuning by analyzing their sampled instrument octave by octave (as a piano tuner does when stretch tuning in the first place), or are they applying an algorithm of, say, x percent per octave to approximate those results?

I think that the issue may be somewhat minimized by the fact that so many of the popular sampled pianos are sampled from large grands, where the stretching that would normally be implemented would be less extreme to begin with, compared to smaller grands (or uprights).

Some interesting info (and some potential red herrings) at these links:

My first DP was a Kurzweil RG 200 (with the Micropiano sound engine in it). It had both stretched and unstretched tuning for the main piano sound. The stretching, in that case, was evidently for brilliance in the upper register, and not for correcting any remaining inharmonicity. I suspect most of the cheaper stretching options on today's DPs are similar. On my RG 200 I usually turned the stretching off - octaves sounded better without, to my ears, that is.

If, especially in a rock band context, you need particular brilliance (which is a kind of detuning anyway) you might try a little chorus or (even better) layering different pianos as an alternative. In a more "acoustic" setting, the key to sound (it seems to me) is rather a suitable PA than some fiddling with stretching.

Variable temperaments, on the other hand, is a very different matter. If you go significantly away from equal temperament you can change the musical atmosphere quite dramatically. But that is another art in itself...

An idea, by the way: Who will be the first to make a DP with aftertouch controlling microtuning of each key? That would be quite a challenge, both for the maker and the players...

An idea, by the way: Who will be the first to make a DP with aftertouch controlling microtuning of each key? That would be quite a challenge, both for the maker and the players...

Since aftertouch affects the tone AFTER you strike the key, it would not work to control tuning (though aftertouch can be used to alter the pitch after the initial strike).

I saw a writeup about a keyboard design that would behave differently depending on where along the key length it was struck. Theoretically that could work for tuning, though I don't know how real-world usable it would be.

Equal P.Only: The stretch tuning is only applied to the piano sounds. Other sounds remain Equal Flat. If a piano sound is layered with a non-piano sound then both sounds are stretched to make sure the tuning is the same for both sounds.

An idea, by the way: Who will be the first to make a DP with aftertouch controlling microtuning of each key? That would be quite a challenge, both for the maker and the players...

I saw a writeup about a keyboard design that would behave differently depending on where along the key length it was struck. Theoretically that could work for tuning, though I don't know how real-world usable it would be.

I'm afraid "flat" and "stretch" have other meanings as what You seem to attribute to them.

Flat is a value-neutral term and subjectively does mean a little bit more "pure" octave than stretch.

On a violine (solo) what you can hear is not "stretch" tuning, but a dynamically adopted "Just" tuning, meaning a trend to play pure intervals. (But the violinist or singer has to preserve the base pitch also by returning to it, so it is always a continuous creative tuning process to play or sing even single melodies.)

Flat is more appropriate for other instruments then Piano, because they have no such physical characteristics as pianos (double copper wired strings in the bass, or undamped resonant strings in the upper octaves).

Ando: Old composers liked their clavichords, they preferred them to harpsichords. Even "gebundene" ("bound", meaning 2 or 3 keys shared) types, but they needed a very demanding technic to play them, because they should have give some expressive potential what possibly is lacking even with our high developed pianos.

I let now build my own acoustic clavichord to see how it feels, in 2-3 Months I can perhaps tell...

anotherscott:

I am thinking on the vibrato playing on violine and other string instruments. Perhaps it is response possible to the general tuning challenge to let the pith flow around the ideal pitch a bit to let the hearers brain to get it right. "Bebung" of clavichord could have had some similer subtle effect.